# Contiguously Increasing Numbers - Amazon Top Interview Questions

### Problem Statement :

```Given two integers start and end, return a sorted list of integers such that every number e is between start ≤ e ≤ end and the digits of e are contiguously increasing. For example, 2345 is contiguously increasing while 135 and 321 are not.

Constraints

0 ≤ start ≤ end < 2 ** 31

Example 1

Input

start = 0
end = 100

Output

[1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 23, 34, 45, 56, 67, 78, 89]```

### Solution :

```                        ```Solution in C++ :

vector<int> solve(int start, int end) {
vector<int> ans;
queue<int> q;
for (int i = 1; i <= 9; i++) q.push(i);

while (!q.empty()) {
int sz = q.size();
while (sz--) {
int cur = q.front();
q.pop();
if (cur >= start and cur <= end) ans.push_back(cur);

if (cur % 10 != 9) {
cur = cur * 10 + cur % 10 + 1;
q.push(cur);
}
}
}

return ans;
}```
```

```                        ```Solution in Python :

class Solution:
def solve(self, start, end):
s = "123456789"
a = []
for i in range(9):
for j in range(i + 1, 10):
x = int(s[i:j])
if start <= x <= end:
a += (x,)
return sorted(a)```
```

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